<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<script>
					
					
					// 1. 数组
					var arr1 = new Array();
					console.log(arr1.length)
					
					arr1[0] = "张三";
					arr1[1] = 1;
					arr1[2] = "王五"
					console.log(arr1)
					console.log(arr1.length)
					
					var arr2 = new Array(3);
					console.log(arr2[0])
					
					var arr3 = new Array(10,20,30,40,50)
					console.log(arr3[0])
					
					var arr4 = [10,20,30,40]
					console.log(arr4)
					
					var arr5 = [
						[1,2,3],
						[4,5,6],
						[7,8,9],
					];
					var stus = [
						{id:1,name:"张三",age:18},
						{id:2,name:"李四",age:19},
						{id:3,name:"王五",age:20},				
					]
					console.log(stus)
					
					
					
					
				</script>
	</body>
</html>